192 



embryo leaves the egg membrane. At the age of four days the embryos 

 had assumed the shape of young Jiipinnaria'. 



By that time I had to leave Tobago; the culture was carried along with 

 the other larval-cultures to Trinidad, but after a few days it was found 

 to be all dead. Accordingly I can give no further information about the 

 shape of the larva; but the fact here established that this species has a 

 typical pelagic larva is in itself of no small interest. — 1 have not thought 

 it worth while giving a figure of the young larva, partly because the few 

 specimens preserved are in a rather poor condition, partly because the 

 larvae are not yet far enough developed for giving any information about 

 the special characters of this larva. 



Asterias calamaria Gray. 



Th. Mortenscn. Devclopinenl of some .Japaiu'so lu-hinoderms; p. f).')!. 



The breeding season of this widely distributed pacific species was found 

 to begin (in Japan) towards the end of June, and fertilization was under- 



Fig. 100. Young Bipinnariae of Asterias calamaria (Fig. A), Pisaster ochraceus (Fig. B), 

 Euasierias Troscheli (Fig. C.) and Orthasterias leptolena (Fig. I).). A— C. '"". ; D. ""/■. 



taken on .June 25th. The development of this species being rather slow, 

 as usually in the Asterids, there was no hope of rearing the larvae to full 

 shape, as I had to leave Misaki already on the 12th of July. By that time 

 the larvae had reached the stage represented in Fig. 100, A. It is, of course, 

 not sufficiently advanced for showing the specific characters, and it is, 

 especially, not to be seen, whether it will develop into a lirachiolaria. The 

 result achieved with this species is then in the main confined to the proof 

 of its having pelagic larvae. I have no notices about the first developmental 

 processes. 



